A number of publications disclose methods for analog display of the weight of the substance being metered, and balances into which such methods are incorporated. For example, German Published Application No. 23 36 045 describes a balance which, besides the usual numeric display, has a non-numeric display indicating which part of the weighing range has already been used, or which part is still available. A similar balance is described in German Patent No. 26 04 747. In this patent, strips of light-emitting material are used to form symbols. However, neither of these balances has a display which actually assists the user in metering predetermined amounts of a substance, unless, coincidentally, the amount to be metered is the same as the available weight range.
Another example is U.S. Pat. No. 4,200,896, This discloses a display having a seven segment indicator in which, when a non-numeric display is desired, only the horizontal segments are activated. As the weight of the substance to be metered increases, the position of the activated horizontal segment changes. This gives the operator an indication of the weight on the balance relative to the desired weight. This type of operation has the advantage that a separate, additional display is unnecessary. It has the disadvantage that the display changes only in a step-wise fashion with decimal steps. Further, it requires greater concentration and effort on the part of the operator to adjust the addition of material to the balance to the logarithmic display change characteristic. These comments apply also to another known method (German Published Application No. 27 02 842) in which the steps are also decimal steps, a non-numeric display with light emitting elements being furnished in addition to the conventional numeric display.
Finally, German Published Application No. 29 23 215 discloses a display consisting of two concentric circles, each formed by a plurality of point sources of light (e.g. light emitting diodes). Each circle is indicative of a particular decimal place or group of decimal places. The light emitting diodes are activated in accordance with the then present weight on the balance, the latter being computed by counting of the activated diodes.